Add Telegram notification support

watchtower/README.md

@@ -21,9 +21,15 @@ the following fields:
 
 
 ### Sanity failure push notification
-To receive a Slack and/or Discord notification on sanity failure, define one or
-both of these environment variables before running `solana-watchtower`:
+To receive a Slack, Discord and/or Telgram notification on sanity failure,
+define environment variables before running `solana-watchtower`:
 ```
 export SLACK_WEBHOOK=...
 export DISCORD_WEBHOOK=...
 ```
+
+Telgram requires the following two variables:
+```
+export TELEGRAM_BOT_TOKEN=...
+export TELEGRAM_CHAT_ID=...
+```

watchtower/src/notifier.rs

@@ -3,28 +3,44 @@ use reqwest::Client;
 use serde_json::json;
 use std::env;
 
+struct TelegramWebHook {
+    bot_token: String,
+    chat_id: String,
+}
+
 pub struct Notifier {
     client: Client,
     discord_webhook: Option<String>,
     slack_webhook: Option<String>,
+    telegram_webhook: Option<TelegramWebHook>,
 }
 
 impl Notifier {
     pub fn new() -> Self {
         let discord_webhook = env::var("DISCORD_WEBHOOK")
             .map_err(|_| {
-                warn!("Discord notifications disabled");
+                info!("Discord notifications disabled");
             })
             .ok();
         let slack_webhook = env::var("SLACK_WEBHOOK")
             .map_err(|_| {
-                warn!("Slack notifications disabled");
+                info!("Slack notifications disabled");
             })
             .ok();
+        let telegram_webhook = if let (Ok(bot_token), Ok(chat_id)) =
+            (env::var("TELEGRAM_BOT_TOKEN"), env::var("TELEGRAM_CHAT_ID"))
+        {
+            Some(TelegramWebHook { bot_token, chat_id })
+        } else {
+            info!("Telegram notifications disabled");
+            None
+        };
+
         Notifier {
             client: Client::new(),
             discord_webhook,
             slack_webhook,
+            telegram_webhook,
         }
     }
 
@@ -42,5 +58,14 @@ impl Notifier {
                 warn!("Failed to send Slack message: {:?}", err);
             }
         }
+
+        if let Some(TelegramWebHook { chat_id, bot_token }) = &self.telegram_webhook {
+            let data = json!({ "chat_id": chat_id, "text": msg });
+            let url = format!("https://api.telegram.org/bot{}/sendMessage", bot_token);
+
+            if let Err(err) = self.client.post(&url).json(&data).send() {
+                warn!("Failed to send Telegram message: {:?}", err);
+            }
+        }
     }
 }